No, an RegEx is an pattern matching system only. There are very little comparing features.

You will need to use an macro/script for that. How that macro will work and what you will get as result depends on your real current needs and how the rest of the line looks a like: are that digits and tabs the only signs in such an line?

Here is an quick example code.Be sure to use this always with copies of your importent documents. Because i don’t have an impression what could get worse. If anyone should improve this script for you we will need an better example how the rest of such an line will look a like.

Ahh, and this script will work only with tabs as delimiter or it have to be adjusted as one needs.

////===== Description: ==================
//// Click into an line and execute this macro/script.
//// The line will split at tab stops
//// and if an part is detected as an number
//// the greatest number is stored as vBiggestNumber for your use.